Airplane-wing-structure truss



G. H. CURTISS.

MHPLANE wma STRUCTURE muss.

APPLHCAHUN FILED MAY 4. |918.

1,351,743. Y Pawndsept. 7, 1920.

Perl-:Nr oFFmE;

@am rr. (umriss, oronnnnn om, `new `anni;nasserron. 'ro connssmornmn ummoron conronnron, A oonronsrron or ,New frenz.

Bpeoloetlon ot YIrefiersPatents.

Application niet! Key 4, 15318. Serial 15in. easing.

eitizenrof 'the United Statesi Vat Garden City, in the oountyo Nassauand State of New York; have 'inventedY certain new and usefulVImprovements inkirplaue- Wing-Structure 1rx1sses,` of 'which thefollowingisas cication. f j

My invention relates vto .airplaneV wing structure trussing systems andis character'- ized by an arrangement oi wiring utilizing n. minlmumnumber of wires. with resulting maximum proportionate stren h. Insteadof providin separate lift and rift wires at opposite si es of thefuselage a single wire in each instance is used. These wires extendsingularly upwardl and rearwardly from the inner ends of t e forward winbeams of the lower wings to the outer en s of the rear wing beams of theup er wings. They take not only a considerab ingly large portion o thedrift load as well. Es ecially 1s the above arrangement adaptab e to thesmaller or speedV scout types of air lanes having a shallow chord andmore or ess limited wing spread. When used in connection with K orsimilar struts (which revent deflection of the win s due to twistmgstrains) trussing of the a ove character is ad nate. x

In t e drawings, wherein like characters of reference designate like orcorresponding parts throughout the several views:

Figure 1 is a perspective view of an airplane having its win -structuretrussed in accordance with the invention herein disclosed.; and

.Fig 2 is an end elevation of the wing'V structure showin the angularityof the combination lift an drift wiring,

The machine illustrated Vis of the biplane type and includes the usualkfuselage 10, landing gear 11, empennage 12, upper supporting surface 13and ower` supporting surface 14. The super sed supporting surfaces areinterconnects bysubstantially K-struts 15. These K-struts are bestsuited to machines of the character disclosed or the reason that theyprevent distortion of the wings due to twisting strains. Moreover theoder a minimum of resistanoeto the air while the machine is in Hight andas the e portion of the u lift load while in flight but a correspondf t'lift wires.

lhave heretofore been used it a much improved trussiuT-system hasaocially 'adapted to 'high yspeed machines such constructionV is preerred.'` 'The invention however Vmay be used in connection withtpl'afnes ormultiplanes generally; the illus- /trationu'ofitsluseinconnection with a biplane-being only by way ofexarjnple.

V Individual drift, ,stager and drop wires have been eliminatedstructure` The K-strts take the place o the jstagger wires usuallyprovided. The

m the win spread fof thewings being more or less small andthe' chordproportionately shallow,`

binedly functionasfhoth lift and drift wires in that they take up aconsiderable portion of both the lift and drift loads while the machineis in iight. They extend angulerly ,wardlyg outwardly and rearwardlyfrom e front wing beams 16 `of the lower wings 14 at the inner` endsthereof (atthe points where the vwings are fsstcnedto the fuselage ,10)to the outer ends ofthe' rear wing beams 17 Vofwthe upper wings 13V (atthe points where theAK-struts 15 engue). By extending-the wires,whiohare esignated as 18, rearwardly the are made to function as driftwires and y extendin them upwardly and outwardl they are ma` e tofunction as `us the single wire lengths at op osito sides of the `inselne serve a twofo d purpose and as a res `t out down the resistance of themachine considerably. In fact, they constitute the only wires which areneeded in the `formation of the wing structure truss-and `as .a numberof wires eordinglyheen evolved e attachment of thejwi 18 at the innerends forwardly of the pointuofattachment ofthe wires at the outerendsisim ortant. Itis this arrange- `ment which ren ers themV useful fortaking updrift strains on the wings.` Especially is the wiringarrangement useful in connection with K or similarfstruts for' thereason that .such struts 'interconnect the superposed wings at 'theirouter Vends `in a manner condueive to absolute rigidity. Furthermore,struts ofthe K typeequally distribute the compression stress upon bothwing beams y ,Patented sepas. '1920.

is evident that Yausging system Ver uns invention -isespe- 4 dro)wiresneedfnot be used. 4In lieu of the 1i of the lower wings. In otherwords, the arrangement disclosed is conducive to maximum strength with`n minimum number of wires, z. e., the ideal truss for airplanes of the seed scout type.

Wlijile I have described my invention n detail in its present preferredembodiment, it will be obvious to those skilled in the nrt afterunderstanding mv invention, that various changes and modifications maybe made therein without de arting from the spirit'or scopo thereof, aimin tho appended claims to cover all auch `modifications und changes.

What is claimed is:

1. A wing structure truss for air )lanes having a single exposed wim ateac side of the fore and aft axis of the craft to care for both the liftand drift stresses, the wire in euch instance being extended rearwardlyand outwardly at an angle.

A. Wing structure truss for airplanes having but two exosed wires tocare for both the lift and (rift stresses, seid wires beingvr arrangedrespectively at opposite sides of the fore and aft axis of the craft toextend rearwardly and upwardly nt an angle.

3. A wing structure truss for airplanes having n. single exposed wire ateach side of the fore andait axis of the craft to cure for both the liftand drift stresses, the wire in each instance being extended rearwardlyand outwardly at an ung-le and being confined in each instance to thegup between the airplane wings.

A wing structure truss for airplanes having but two exposed wires tocure for both the lift und drift stresses, said 4wires being arrangedres ectively at opposite sides of the fore and a axis of the craft toextend rearwardly and upwardly at an angle and being in each instanceconfined to the gap between the airplane wings, the wires at theirforward lower ends connecting with the front wing beams of the lowerwings and at their upper rearward ends with the rear wing beams of the u`Jer wings.

In testimony whereof lpliereunto aliix my signature.

GLENN H. CURTISS.

